No rake db:test:* commands in my Rails rake. Where may I find all missing rake commands?

In Rails Guides
(http://guides.rubyonrails.org/testing.html#preparing-your-application-for-testing)
they mention some "rake db:test:load" command and other "rake db:test:*"
commands. But when I do "rake -D db" or "rake -T" there is no any "rake
db:test" in the output.

It makes me think that there are dozens of rake commands that are not
distributed when I do "rake -T" (Display the tasks (matching optional
PATTERN) with descriptions) or "rake -D task" (Describe the tasks
(matching optional PATTERN) with descriptions).

Is there one special place where ALL Rails rake commands are presented
with full explanation for them? Some Rake API?

not that I know of. the issue with trying to document such a list is that rake isn’t an API, it’s a general utility for automating tasks. rake tasks can be defined and created by gems, you can also create your own. Therefore, it would be difficult to document them all in one place, they’re usually documented with the functionality they support. For example, the edge guide on migrations documents rake tasks related to migrations.

There is an overview of the rake commands and the various categories of tasks that are provided in the default rails bundle at the following:

http://edgeguides.rubyonrails.org/command_line.html#rake